Monthly Archives: April 2025

In petrochemical plants, equipment like piping, vessels, and heat exchangers operate under harsh conditions that slowly degrade their integrity. Without early detection, these issues can lead to unplanned shutdowns, environmental risk, and massive repair costs.

Based on API 571, here are five of the most critical damage mechanisms affecting fixed equipment — and how to detect and manage them early using modern tools like RBLX™.

5 Critical Damage Mechanisms in Petrochemical Plants

🔹 1. Corrosion Under Insulation (CUI)

What it is:
CUI occurs when water penetrates damaged insulation and causes corrosion on the metal surface underneath. It’s often hidden and one of the most underestimated threats.

Where it happens:

• Carbon steel and low-alloy steel piping
• Operating between 50°C and 175°C
• Outdoor piping, steam-traced lines, or areas with degraded insulation

How to detect it early:

• Identify CUI-prone assets in RBLX-RBI
• Use guided wave UT, visual inspection, or profile RT
• Track corrosion history and inspection intervals in RBLX-IDMS
• Define CUI Integrity Operating Windows (IOWs) for moisture/temperature control

🔹 2. Stress Corrosion Cracking (SCC)

What it is:
SCC is cracking that occurs due to a specific corrosive environment and tensile stress. It’s often difficult to detect until it leads to failure.

Common types:

• Chloride SCC in stainless steels
• Caustic SCC in carbon steel exposed to caustic solutions

Where it happens:

• Heat exchanger tubes
• Caustic or amine service lines
• Welded zones without proper post-weld heat treatment (PWHT)

How to detect it early:

• Flag SCC risks in RBLX™ based on service and material
• Use TOFD, PAUT, or WFMT for early-stage detection
• Schedule focused inspections using RBI logic
• Keep SCC service history and material stress logs updated in RBLX-IDMS

🔹 3. High Temperature Hydrogen Attack (HTHA)

What it is:
HTHA is a form of degradation that occurs when hydrogen at high temperatures diffuses into steel and reacts with carbides, causing internal damage.

At-risk range:
Above 400°C (750°F) in high-pressure hydrogen environments

Where it happens:

• Hydrogen reformers
• Hydrotreaters
• Reactors in hydrogen-rich service

How to detect it early:

• Use RBLX to evaluate risk zones based on material, temperature, and hydrogen exposure
• Apply Advanced Ultrasonic Backscatter (AUBT) and replica testing
• Conduct fitness-for-service evaluations with RBLX and FITest-FFS™

🔹 4. Sulfidation (Sulfidic Corrosion)

What it is:
Sulfidation happens when sulfur compounds in process streams react with metal surfaces, forming sulfides that weaken the structure.

Risk zone:
Between 260°C and 540°C (500°F to 1000°F)

Where it happens:

• Furnace tubes
• Transfer lines
• Crude and vacuum distillation units

How to detect it early:

• Identify low-silicon carbon steels in service using RBLX material database
• Monitor corrosion rates through UT scans
• Plan targeted inspections using RBLX-RBI based on sulfur exposure
• Log findings in RBLX-IDMS for long-term monitoring

🔹 5. Erosion-Corrosion

What it is:
A combined effect of mechanical wear and corrosion, caused by high-velocity or turbulent flow — especially when carrying solids or vapor-liquid mixtures.

Where it happens:

• Elbows, reducers, and tees
• Pump impellers
• Two-phase flow piping and slurry lines

How to detect it early:

• Model erosion risk zones in RBLX pipeline/piping module
• Monitor flow data and turbulence points
• Use UT mapping or profile RT
• Track wall loss trends and corrective actions in RBLX-IDMS

💡 Smarter Damage Management with RBLX™

RBLX™ software supports proactive risk management by aligning with API 571, API 580, and API 581. It enables engineers and inspectors to:

• Identify damage mechanisms per material and environment
• Assign inspection methods (UT, TOFD, PAUT, RT, etc.)
• Automate inspection planning based on risk
• Track corrosion rates, inspection results, and IOWs
• Integrate with CMMS, FITest-FFS, and field tools

✅ Take Action Before Damage Happens

These mechanisms are predictable and preventable. With the right RBI tools, your team can move from reactive inspections to strategic, cost-saving decisions.

📩 Want to see how RBLX™ can help your facility?
👉 Request a demo at lteng.co.uk/contact or email info@lteng.co.uk

🔑 Keywords for SEO:

• API 571 Damage Mechanisms
• Corrosion Under Insulation (CUI)
• Stress Corrosion Cracking (SCC)
• Sulfidation in Carbon Steel
• Erosion-Corrosion Prevention
• High Temperature Hydrogen Attack Detection
• RBI Software for Petrochemical Plants
• Asset Integrity Management Software
• Inspection Data Management System (IDMS)

🏭 Why Age Matters in RBI

Not all facilities are created equal. When it comes to Risk-Based Inspection (RBI), the age of the plant, condition of its assets, and availability of integrity data can drastically change the inspection strategy.

New facilities often start with limited inspection history but well-documented design and materials.
Older facilities may have legacy systems, undocumented changes, and decades of operation — with corrosion and wear already in progress.

With the right RBI software (like RBLX™), both scenarios can be managed effectively — but the approach must change.

🆕 RBI in New Facilities

New assets offer a clean slate — but that doesn’t mean they’re low-risk.

Key RBI Considerations:

• 🔍 Unknown initial corrosion behaviour
• 🧱 Limited inspection history
• 🧾 Manufacturer data must be trusted (for now)
• 📉 Design data available for estimating POF/COF

Strategy:

✅ Use API 581 models with conservative assumptions
✅ Define baseline corrosion loops
✅ Install corrosion monitoring devices early
✅ Set shorter initial inspection intervals, extend later based on findings

Role of RBLX™:

• Build the full equipment hierarchy from day one
• Link to CCD, IOWs, and design specs
• Establish corrosion loops and IOW alerts for each system
• Assign initial RBI plans with built-in templates

🏚️ RBI in Aging Facilities

Older plants present different challenges — and bigger opportunities for inspection savings and safety improvements.

Challenges:

• ⚠️ Hidden corrosion/damage mechanisms
• 📉 Incomplete inspection history
• 🧩 Material changes or undocumented repairs
• ❗ Higher POF due to cumulative wear and process variability

Strategy:

✅ Use actual wall thickness and historical inspection data
✅ Reassess every loop for updated mechanisms (API 571)
✅ Apply semi-quantitative or quantitative RBI
✅ Identify NII opportunities to reduce outage costs

Role of RBLX™:

• Import years of thickness and inspection data into RBLX-IDMS
• Flag overdue or high-risk items
• Visualize remaining life across circuits
• Recommend NII alternatives based on historical data and HOIS RP103 logic

🔍 Comparison Summary

💡 Real-World Takeaway

Whether your site is 30 weeks old or 30 years old, RBI is essential. But the path to reliability, safety, and cost efficiency must be tailored to:

• ⚙️ Equipment condition
• 🧪 Known damage mechanisms
• 📊 Data maturity

That’s where a flexible, standards-based platform like RBLX™ makes the difference.

📩 Have a new asset or old facility you want to optimize?
Request a demo: lteng.co.uk/contact
📧 Or email: info@lteng.co.uk

🔍 SEO Keywords:

• RBI for new facilities
• RBI for aging assets
• Risk-Based Inspection in oil and gas
• RBI software for brownfield sites
• RBI in greenfield projects
• Asset integrity old vs. new
• Corrosion loop planning new plants
• Inspection software for refineries
• RBLX RBI tool
• Plant lifecycle inspection strategy

How plants stay safe, reliable, and cost-effective — and how RBLX™ helps make it happen.

Why Asset Integrity Management Matters

Pipelines, pressure vessels, tanks, and exchangers are the heartbeat of oil, gas, and industrial plants. But they face constant threats: corrosion, cracking, leaks, fatigue, and more.

Asset Integrity Management (AIM) is the structured process of ensuring these critical assets operate safely, efficiently, and without unplanned failures — throughout their entire lifecycle.

Whether you run a new facility or a decades-old plant, AIM is the foundation of:

• Safe operations
• Compliance with standards (API, ASME, HSE)
• Reduced downtime and maintenance costs
• Long-term asset reliability

What’s Included in an Integrity Program?

Effective AIM includes several interconnected systems and practices. Here’s what a typical program looks like — and how they all work together:

1. Risk-Based Inspection (RBI)

RBI is about inspecting based on risk, not just time. It helps prioritize assets that matter most and safely extend inspection intervals for low-risk equipment.

Tools like RBLX™ follow API 580/581 and generate:

• Probability and consequence of failure
• Risk ranking
• Inspection plans tailored to each asset
• Updated intervals and inspection types

2. Inspection Data Management System (IDMS)

An IDMS tracks all inspection results, wall thickness readings, NDT reports, and historical data — all in one system.
In RBLX™, IDMS is integrated directly with RBI, so your inspection decisions are always based on up-to-date field data.

3. Corrosion Control Document (CCD)

CCD organizes your facility into corrosion loops based on fluid, material, temperature, and more.
This helps you manage corrosion risks and plan inspections smarter.

RBLX™ offers a built-in CCD module with:

• Corrosion loop builder
• Damage mechanism library (based on API 571)
• Mitigation strategies and inspection linkages

4. Non-Intrusive Inspection (NII)

NII allows certain inspections to be done without opening equipment — saving time, cost, and risk.

RBLX™ helps determine whether NII is suitable using guidelines from HOIS RP103, and can compare:

• IVI (Internal Visual Inspection)
• NII (UT, PAUT, MFL, etc.)
• Confidence levels for inspection outcomes

5. Integrity Operating Windows (IOWs)

IOWs define safe ranges for process parameters like pressure, temperature, flow, and pH.
If these go out of range, it may trigger corrosion or damage.

With RBLX™, you can:

• Monitor Tier 1–3 IOWs
• Get real-time alerts when limits are exceeded
• Recalculate risk and inspections accordingly

6. Pipeline Integrity Management Syatem (PIMS)

Pipelines require a specialized approach. RBLX™ includes PIMS tools to:

• Assess internal and external threats
• Model time-dependent degradation
• Recommend inspection points
• Track anomalies and wall loss
• Generate pipeline risk profiles

7. Damage Mechanism Review (DMR)

Every asset is exposed to certain threats — from pitting to HTHA.
RBLX™ offers a built-in API 571 DMR engine that:

• Suggests damage mechanisms based on service and materials
• Guides inspectors on what to look for
• Connects to CCD, RBI, and inspection planning

Why an Integrated Approach Matters

In many companies, each of these components exists — but in separate spreadsheets, folders, or tools. This slows down decision-making and increases risk.

RBLX™ unites them in one platform, helping:

• Inspection teams plan smarter
• Engineers respond faster
• Managers see risk clearly
• Companies cut maintenance costs without cutting safety

Real Benefits of an AIM System like RBLX™

Ready to improve your integrity strategy?
Request a demo of RBLX™: lteng.co.uk/contact
info@lteng.co.uk

🔍 SEO Keywords Included:

• What is Asset Integrity Management
• AIM software for oil and gas
• RBLX asset integrity system
• Risk-based inspection explained
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• IOW software API 584
• CCD corrosion control document
• NII vs IVI inspection
• RBI and IDMS integration

Damage mechanism software API 571